In conventional recording methods for optical discs having a plurality of recording layers, when test recording is performed in the recording layers, test recording areas are formed in adjacent recording layers in locations that overlap in the thickness direction. Moreover, the optimal recording power is determined for each recording layer without consideration of the effects of adjacent recording layers. Consequently, what is determined to be the optimal recording power sometimes differs slightly from the true value because of the effects of adjacent layers.
A proposed solution to this problem is to check the usage status of the test areas in recording layers other than the layer in which information (user data) will be recorded, particularly in upper recording layers (disposed on the side toward the optical pickup), before performing the test recording in the layer in which the information will be recorded (see, for example, Patent Document 1).
Patent Document 1: Japanese Patent Application Publication No. 2000-311346 (FIGS. 1 to 8)